Traditionally, vehicle audio systems deliver an audio signal to speakers positioned in the perimeter surfaces of a passenger of a vehicle, such as the doors or a dashboard of the vehicle. An audio signal supplied by a vehicle radio (or other signal source) is amplified, processed, and corresponding acoustic energy is delivered through the speakers to an occupant of the vehicle. In addition, speakers may be located near the ears of the occupant, such as behind the occupant in the headrest or seatback of a vehicle seat or in a rear shelf or other surface adjacent to the rear of the seat. In such systems, speakers positioned behind the head of the occupant radiate acoustic energy directly to an intended listening position of the occupant. The quality of the sound image at the listening position of the occupant depends on numerous factors, including localization of the sound image. Sound localization includes the listener's ability to identify the origin or location of the acoustic energy.